In order to make their flight as pleasant as possible for passengers in a modern commercial aircraft a very wide range of different electronic entertainment devices are increasingly being used on board the aircraft. Nowadays it is already usual for a screen to be made available to each passenger, irrespective of class, so that the passenger can watch films or play games. Each passenger can tune in to a video program or another use of his or her choice, by means of an operating unit. In addition sound playback is also possible, for example film sound, music programs or the like, by means of a headset or headphones connected to the electronic equipment. The entire spectrum of such functions and applications is referred to as ‘in-flight entertainment’ (IFE). A further important and similar area of use is communication on the part of passengers by telephone or Internet on board the aircraft. IFE uses require the transmission of video or audio data from one or more central server units in the fuselage of the aircraft (hereinafter also referred to by the term ‘computing units’) to a respective electronic system connected to the screens and other reproduction or input devices.
The predominant situation provides that the video and audio programs are transmitted synchronously only at given time intervals and for all passengers (broadcast method) but it is felt to be advantageous for such programs to be played on an individual basis (on-demand method). Finally in its entirety a modern in-flight entertainment system in a relatively large passenger aircraft results in a very large amount of data and therefore requires data lines which can implement broadband transmission of video and audio data or the like to a large number of passenger seats.
In addition to the required data line bandwidth to the passenger seats the cabin of a modern commercial aircraft must afford the option of rapid reorganisation in order to completely re-configure it during a short stay between two flights. Re-configuration for example involves re-arranging the passenger seats from a three-class layout to a purely economy layout. For that purpose, it is necessary to move, introduce and remove seat positions which are fixed to the cabin floor in seat rails which are let thereinto. Therefore removing and fitting a passenger seat in the cabin always requires a data line connection to be disconnected and restored.
As an alternative, wireless transmission from the computer unit to the individual passenger seats by means of conventional wireless network devices involving transmission frequencies of 2.4 or 5 GHz (IEEE 802.11a, 802.11b, 801.11 g etc) is admittedly possible, but to achieve the necessary data bandwidth it would be necessary to have a large number of network access points which, by virtue of the necessary, comparatively high transmission power, result in a high level of radiation loading. It is also not out of the question that devices which passengers have brought into the aircraft cabin and which operate on those or adjacent frequencies are switched on by mistake during the flight and interfere with the wireless network. There is also some dispute as to whether the radiation from access points is harmless to people.
Therefore the object of the present invention is to reduce or eliminate one or more of the specified disadvantages. In particular the object of the present invention is to provide a possible way of implementing robust flexible data transmission in a vehicle, in particular in an aircraft.
The object of the invention is attained by a method of transmitting data in a vehicle, wherein a computing unit passes data to a plurality of transmitting and receiving units, wherein the wireless transmitting and receiving units alternately communicate with at least one electronic device having a transceiver unit, and wherein the transmitting and receiving units and the transceiver unit are operated at an operating frequency of more than 30 GHz.
Using wireless transmitting and receiving units for sending data to electronic devices is advantageous as the fixed wiring of an electronic device is eliminated and spatial re-positioning thereof involves a lesser degree of complication and expenditure. A transceiver unit is to be interpreted as being a network device which can wirelessly communicate alternately with a transmitting and receiving unit. In order to achieve higher bandwidths or to service a plurality of electronic devices further wireless transmitting and receiving units can be connected at any time to the data-carrying unit. Network coverage can be optimised by individually distributing wireless transmitting and receiving units. By virtue of using an operating frequency which is markedly above that of conventional wireless access points, it is possible to exclude interference due to for example portable computers with integrated wireless network functionality. Admittedly the range of the signal falls due to a great increase in frequency but the attainable bandwidth in the transmission mode rises. The result of this is that broadband data transmissions can be implemented with wireless transmitting and receiving units involving an operating frequency of more than 30 GHz over short distances with a low level of electrical power consumption and as a result a low level of radiation intensity.
It is possible for example for the ceiling of a cabin of an aircraft to be equipped over a large area with such wireless transmitting and receiving units which can each only reach passenger seats in their relatively close proximity. In spatial terms the levels of radiation concentration are lower than when using conventional wireless network access points with a higher radiation power with a comparable bandwidth but a greater range. The adverse effect on the health of people in the immediate proximity of the transmitting and receiving units is reduced as a result.
It is particularly advantageous to use an operating frequency in the range of between 56 GHz and 64 GHz. At the present time that represents a possible optimum in regard to manufacturing costs, bandwidth provided and structural size. When using an operating frequency from that range it is possible to embody very compact electronic components in which the transmitter, the transmission amplifier and further peripherals are arranged on a single silicon chip.
In a particularly preferred feature a respective electronic device is associated with each transmitting and receiving unit. Thus the transmission power of each transmitting and receiving unit can be minimised by restricting the bandwidth to be transmitted and the distance to be bridged over.
In a further preferred feature a group of a plurality of electronic devices is associated with a transmitting and receiving unit and the electronic devices communicate alternately with the transmitting and receiving unit using different channels. That results in a reduction in the number of transmitting and receiving units to be provided and reduces costs.
In an advantageous embodiment the transmitting and receiving units and the at least one electronic device are further connected to antennae and/or have antennae which are adapted to multi-path emission. In that way an individual antenna can receive data streams from a plurality of spatial directions or emit same and thereby improve the communication properties.
It is preferred for the electronic device to be integrated into a seat or into a group of seats. In that way it is possible for example for data for entertainment programs to be transmitted within the vehicle to devices which are associated with an individual seat or passenger and connected to screens and the like. That means that an electronic device can be associated with each passenger or each small group of passengers in order to simplify data transmission and to provide capacities for the conversion of received data into reproducible signal formats. Furthermore arranging the electronic device in or on the seat is a structure which saves space and which does not have an adverse effect either on the amount of space available for passengers or gangways.
Arranging the antenna of the electronic device at the top of a backrest of the seat is desirable as in that way the distance to be covered between a transmitting and receiving unit at the ceiling of the vehicle is minimised and reception of the data signals can be improved.
Equally arranging the antenna of the electronic device at the underside of a backrest of the seat is advantageous as the distance to be covered between an antenna of a transmitting and receiving unit arranged for example at the floor of the vehicle is reduced.
It is moreover advantageous for the antenna of the transmitting and receiving units to be arranged above the transceiver units, in particular at the ceiling of the vehicle. That can provide for accurate alignment of the antennae with the antennae of the electronic devices in order in that way to enhance the quality of transmission.
Furthermore it is desirable for the antenna of the transmitting and receiving units to be arranged beneath the transceiver units, in particular at the floor of the vehicle. In combination with antennae of transceiver units, which are arranged closely above the floor of the vehicle, the distance to be covered can be further minimised.
The object of the invention is further attained by a system for transmitting data in a vehicle, comprising a plurality of wireless transmitting and receiving units for transmitting and receiving data, a computing unit for passing data to the transmitting and receiving units, at least one electronic device having a transceiver unit for alternate communication with the wireless transmitting and receiving units, wherein the wireless transmitting and receiving units and the transceiver unit are operated at an operating frequency of more than 30 GHz. The further features and advantages are to be found in the configurations of the method of transmitting data in a vehicle.
The object of the invention is also attained by an electronic device for alternate wireless communication with an associated transmitting and receiving unit for transmitting data in a vehicle, in particular in an aircraft, which are passed by a computing unit to a plurality of transmitting and receiving units, which includes a transceiver unit, wherein the transceiver unit is operated at an operating frequency of more than 30 GHz.
The object of the invention is further attained by a transmitting and receiving unit for alternate wireless communication with at least one electronic device having a transceiver unit for transmitting data in a vehicle, in particular in an aircraft, which are passed by a computing unit to a plurality of transmitting and receiving units, wherein the transmitting and receiving unit is operated at an operating frequency of more than 30 GHz.